介孔组装体Alq3-MCM-41的光学性质

将有机发光小分子8-羟基喹啉铝(Alq₃)组装进介孔MCM-41中,采用XRD、IR、荧光光谱等测试方法对组装体Alq₃-MCM-41进行表征。XRD表明,Alq₃-MCM-41保持了有序的介孔骨架结构;IR谱图中,在波数1542 cm^-1处出现的特征吸收谱带表明组装体中Alq₃在孔道中与羟基成键;荧光光谱表明,组装体中MCM-41与Alq₃分子间发生了能量转移,从而使Alq₃-MCM-41具有优异的发光性能;荧光强度随组装量的增多而显著增强,这主要是由于在Alq₃-MCM-41中,MCM-41有序孔道的微环境使Alq₃分子分散性提高,减弱了Alq₃分子间的聚集或缔合现象,从而有效地提高了其发光强度。

The Luminescent Property of Alq3-MCM-41 Assembly

Small organic luminescent molecule of 8-hydroxyquinoline aluminum (Alq_3) as an active optical guest was incorporated into the one-dimension channels of MCM-41.The assemblies were characterized by means of XRD,IR and PL.The results from XRD patterns suggest that the Alq_3-MCM-41 also have the typical mesoporous structure,but the channels were partially destroyed by the entrance of Alq_3.The appearance of absorption band at 1 542 cm~(-1) in IR absorption spectra shows that there is strong binding force between MCM- 41 and Alq_3 in the assembly.As a result of the existence of Alq_3,both of the Alq_3-MCM-41 and the mechani- cal mixture have a strong absorption of the excitated light,although the form is different.In the former the Alq_3 is bonded with the hydroxyl of MCM-41,while in the latter it is physically adsorbed in the surface.Alq_3- MCM-41 has excellent luminescent property owing to the energy transfer between the host and the guest,which is mainly due to the mutual effect of the hybrid inorganic-organic material,and the luminescent intensity strengthens significantly as the content of Alq_3 increases.So the luminescent efficiency is improved corre- spondingly.When it is up to 0.60 g,the relative intensity is as strong as that of the Alq_3 powder.The micro- environment in the ordered channels of MCM-41 increases the dispersion of Alq_3 molecules,decreasing the aggregation among the molecules,and then the luminescence intensity is effectively enhanced.It also can be seen that MCM-41 is a good host for the Alq_3 molecule.The assembly synthesized has the advantage of both the inorganic mesoporous material MCM-41 and the organic Alq_3,so Alq_3-MCM-41 has a good heating, chemical and mechanical stability,it also has a strong luminescent efficiency.Thus the assembly having a steady luminescent property will make a new way for Alq_3 in the application in electronic apparatus and establish a firm base for the synthesis of luminescent materials with excellent properties.